الخلاصة:
The present work explores the structural, electronic and optical properties of the wurtzite MoX2
(X=S,
Se, Te) binary alloys. The calculations were performed using density functional theory (DFT) within
full-potential linearized augmented planes waves (FP-LAPW) method implemented in the Wien2k
package. First, the structural properties such as the lattices parameters a andc with bulk modulus B and
first pressure derivative B’ are determined from three distinguished approximations PBE-GGA, PW-
LAD and WC-GGA. When X is moved at S, Se and Te atoms the lattice a increases and c parameter
increases. Second, the electronic properties like direct and indirect bandgap of MoS2
, MoSe2
and
MoTe2
are investigated using both PBE-GGA and TB-mBJ approximations. The results shows that the
binary alloys are semiconductors with direct bandgap energy. The gap decreases if X moves to S, Se
and Te atoms. Third, the optical properties such as real and imaginary parts with the refractive index of
the ternary alloys are predicted in this study. The curves of optical properties shift toward the higher
energies with augmentation in their amplitudes.
